Spiru Haret

Spiru Haret
Born	Spiridon Haret (1851-02-15)15 February 1851 Iași, Moldavia
Died	17 December 1912(1912-12-17) (aged 61) Bucharest, Kingdom of Romania
Resting place	Bellu Cemetery, Bucharest, Romania
Nationality	Romanian
Education	Saint Sava National College
Alma mater	University of Bucharest University of Paris
Known for	N-body problem Romanian education system
Spouse	Ana Popescu ​ (m. 1883)​
Scientific career
Fields	Mathematics, Astronomy
Institutions	University of Bucharest School of Bridges and Roads
Thesis	Sur l’invariabilité des grandes axes des orbites planétaires (1878)
Doctoral advisor	Victor Puiseux
Minister of Religious Affairs and Public Instruction
In office 31 March 1897 – 30 March 1899
Prime Minister	Dimitrie Sturdza
Preceded by	George Mârzescu
Succeeded by	Take Ionescu
In office 14 February 1901 – 20 December 1904
Prime Minister	Dimitrie Sturdza
Preceded by	Constantin C. Arion
Succeeded by	Mihail Vlădescu
In office 12 March 1907 – 28 December 1910
Prime Minister	Dimitrie Sturdza Ion I. C. Brătianu
Preceded by	Constantin Istrati
Succeeded by	Constantin C. Arion
Interior Minister
In office 13 December 1904 – 20 December 1904
Prime Minister	Dimitrie Sturdza
Preceded by	Vasile Lascăr
Succeeded by	Gheorghe Grigore Cantacuzino

Spiru C. Haret (Romanian pronunciation: [ˈspiru haˈret]; 15 February 1851 – 17 December 1912) was a Romanian mathematician, astronomer, and politician. He made a fundamental contribution to the n-body problem in celestial mechanics by proving that using a third degree approximation for the disturbing forces implies instability of the major axes of the orbits, and by introducing the concept of secular perturbations in relation to this.

As a politician, during his three terms as Minister of Education, Haret ran deep reforms, building the modern Romanian education system. He was made a full member of the Romanian Academy in 1892.

He also founded the Bucharest Astronomical Observatory, appointing Nicolae Coculescu [ro] as its first director. The crater Haret on the Moon is named after him.